1. Field of the Invention
This invention relates generally to forceps insertable through a small opening and usable without expanding the opening and, more particularly, to surgical forceps in which the tips may be opened and closed without changing the exterior size of the body of the forceps.
2. Description of the Prior Art
In order to decrease unnecessary risk to a patient, it is oftentimes desirable to refrain from undertaking major surgical procedures. Avoiding major surgery by providing out-patient treatment whenever possible, is becoming an increasing practice. Such treatment has been proven to be successful and highly desirable since disruption of the patient's normal activity is lessened.
One area in which major surgery can be avoided is in the removal of common duct stones. Therein, rigid forceps may be required in order to permit passage through a duct system having a midline opening in the sinus tract or in order to crush large stones into easily removable smaller fragments. Since the ducts are often relatively small and since the forceps are inserted a substantial distance into the patient, the forceps must be constructed so that they do not damage the ductal tissues when they are opened and closed. The use of suitable rigid forceps under fluoroscopic control may eliminate the need to make large incisions to remove stones which otherwise may be removed through a relatively small incision with proper manipulation of the forceps.
Forceps for firmly grasping objects are generally constructed by pivotally connecting the body portions between the tips and the handles in a manner similar to that commonly utilized in constructing a pair of pliers. However, the use of forceps of this type is often prevented when the forceps are to be inserted into relatively small passages, since the size of the body of the forceps increases when the tips are opened.
Forceps of a somewhat general character to those of the applicant are shown in Hulka U.S. Pat. No. 3,291,641. Therein, the halves of the forceps are connected together by a hinge assembly like that employed in hanging a door. The construction of the Hulka hinge assembly is much more complex than that shown herein and is more difficult to disconnect for sterilization. In addition, the size of the body increases slightly when tips are closed.